What is the role of enzymes in biological reactions?

What is the role of enzymes in biological reactions?

• A. They are consumed in the reactions they catalyze.
• B. They require RNA templates to function.
• C. They act as biological catalysts, changing the rate of chemical reactions without being consumed.
• D. They are the primary source of genetic material.

Answer: (C)

Enzymes act as biological catalysts that speed up chemical reactions by lowering the activation energy needed to reach the transition state, so reactions proceed much faster under normal cellular conditions. They are not consumed in the process; after the reaction they return to their original form and can catalyze many more reactions. This specificity comes from the active site, where a substrate binds in a way that is highly selective, often explained by the induced-fit concept where the enzyme slightly changes shape to fit the substrate. Enzyme activity is influenced by factors like temperature, pH, and the presence of cofactors or inhibitors that can alter the enzyme’s shape or the availability of the active site. The other statements don’t fit: enzymes aren’t consumed during reactions, and while some RNA molecules can have catalytic roles (ribozymes), most enzymes are proteins and do not require RNA templates to function. Enzymes are not the primary source of genetic material.

Enzymes act as biological catalysts that speed up chemical reactions by lowering the activation energy needed to reach the transition state, so reactions proceed much faster under normal cellular conditions. They are not consumed in the process; after the reaction they return to their original form and can catalyze many more reactions.

This specificity comes from the active site, where a substrate binds in a way that is highly selective, often explained by the induced-fit concept where the enzyme slightly changes shape to fit the substrate. Enzyme activity is influenced by factors like temperature, pH, and the presence of cofactors or inhibitors that can alter the enzyme’s shape or the availability of the active site.

The other statements don’t fit: enzymes aren’t consumed during reactions, and while some RNA molecules can have catalytic roles (ribozymes), most enzymes are proteins and do not require RNA templates to function. Enzymes are not the primary source of genetic material.